%I #3 Oct 01 2013 17:57:58
%S 11,73,443,1031,2339,11833,56737,122891,5423669
%N Numbers n such that 2^n-th prime + 2^(n-1)-th prime + 1 is prime.
%e prime(2^2)+prime(2^1) + 1 = 11 = prime.
%o (PARI) f(n)= for(x=1,n,y=prime(2^x)+ prime(2^(x-1))+1;if(isprime(y),print1(y",")))
%K hard,nonn
%O 1,1
%A _Cino Hilliard_, Feb 20 2004
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